# Homework Help: Set logic homework

1. Aug 19, 2010

1. The problem statement, all variables and given/known data
X={n/n belongs to N,X>=4}
B={x belongs N/ x<5}

2. Relevant equations
then,
A intersection B=________

2. Aug 19, 2010

### Office_Shredder

Staff Emeritus
Re: set,logic

Your post has several errors in it. There's no A until the final line of your post and your set X contains only elements such that X>=4 which doesn't make any sense.

I assume your intended question is
$$A= \{x\ :\ x\in \mathbb{N}\ &\ x\geq4 \}$$
$$B=\{x\ :\ x\in \mathbb{N}\ &\ x<5 \}$$

and you want to find $$A\cap B$$

You have to show what work you've done so far. How have you tried to solve the problem?

3. Aug 19, 2010

### HallsofIvy

Re: set,logic

Assuming, as Office Shredder suggests, that your sets are
$A= \{n |n\in \mathbb{N} , \ n\ge 4\}$
and
$B= \{n| n\in \mathbb{N} ,\ n< 5\}$

Can you list some members of A and b? What natural numbers are greater than or equal to 4? What natural numbers are less than 5?

4. Aug 20, 2010

### dharavsolanki

Re: set,logic

The problem is solved already. Look at the last post. I guess the problem right now is that you are attempting to imagine or list down the members...

Lesson Learnt:
Step 1 : imagine the set constraints/description
Step 2 : List the ocntents of the set and imagine a pattern